The invention relates to a nonwoven mat as half-stuff which contains a high performance thermoplast as melt fibre and a reinforcing fibre, and also a method for producing a nonwoven mat of this type and fibre composites produced from the nonwoven mat.
The production of nonwovens by the wet method in typical modes of operation derived from paper production is known in the state of the art. In “Nonwovens”, Viley-VCH, Viley-VCH Press, Weinheim 2000, from page 235 ff., a method of this type is described. The method is thereby implemented such that the fibres are dispersed in water, then a continuous nonwoven formation is effected on a wire belt by filtration and subsequently compaction, drying and rolling-up of the formed nonwoven web is undertaken.
Methods of this type are used essentially for paper production, such as e.g. synthetic fibre paper, teabag paper, air filter paper or also cigarette covering papers.
The method of the state of the art was hence applied only for the production of special papers or special technical nonwovens as end product.
Moulded articles are also known from the state of the art which were formed from melt fibres and a reinforcing fibre. A moulded article is disclosed in EP 0 774 343 A1 which comprises a core layer and a cover layer, the core layer being formed from melt fibres and a reinforcing fibre. It has however been shown that this moulded article is suitable only for the purpose of use mentioned in the above European application. The moulded article according to EP 0 774 343 A1 has in fact inadequate properties with respect to density and strength and is hence limited in its applicability.
It is therefore the object of the present invention to provide a novel nonwoven mat which is suitable as half-stuff for producing fibre composites with high density. Furthermore, it is an object of the present invention to indicate a method in this respect for producing a nonwoven mat of this type. The method is intended furthermore to have great variability, with respect to the usable components and the properties which can be achieved therewith.